cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A370253 Number of deranged matchings of 2n people with partners (of either sex) such that at least one person is matched with their spouse.

Table of values

n a(n)
0 0
1 1
2 1
3 7
4 45
5 401
6 4355
7 56127
8 836353
9 14144545
10 267629139
11 5601014255
12 128455425593
13 3203605245777
14 86317343312395
15 2498680706048191
16 77336483434140705
17 2548534969132415297
18 89087730603300393443
19 3292572900736818264015
20 128281460895447809211529

List of values

[0, 1, 1, 7, 45, 401, 4355, 56127, 836353, 14144545, 267629139, 5601014255, 128455425593, 3203605245777, 86317343312395, 2498680706048191, 77336483434140705, 2548534969132415297, 89087730603300393443, 3292572900736818264015, 128281460895447809211529]

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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